Comparative intake of white- versus orange-colored maize by Zambian children in the context of promotion of biofortified maize.

BACKGROUND: Vitamin A deficiency is associated with poor health outcomes related to reproduction, growth, vision, and immunity. Biofortification of staple crops is a novel strategy for combating vitamin A deficiency in high-risk populations where staple food intakes are high. African populations are proposed beneficiaries of maize (Zea mays) biofortified with provitamin A carotenoids, often called "orange maize" because of its distinctive deep yellow-orange kernels. The color facilitates ready recognition but presents a cultural challenge to maize-consuming populations, including those in much of Africa, who traditionally eat white varieties. OBJECTIVE: This study explores the intake patterns of, as well as adaptation to, traditional foods made with provitamin A-biofortified maize compared with white maize in rural Zambian children 3 to 5 years of age (n = 189) during a 3-month feeding trial. METHODS: The subjects were fed a breakfast of maize porridge (sweet mush), a lunch of maize nshima (stiff mush) with various side dishes, and an afternoon snack based on a 6-day rotating menu. The trial was conducted in 2010. The orange maize used in the trial came from three different sources. O1 maize was from the 2009 harvest and was stored in a freezer until use in 2010. O2 maize was also from the 2009 harvest and was stored in a cold room until 2010. O3 ("fresh") maize was from the 2010 harvest and was fed immediately after harvest in week 9 of the study and then stored in a freezer until milling for the final four weeks. RESULTS: Consumption of menu items, except snacks, was influenced by week (p < .0084). The intakes of porridge and nshima made with orange maize equaled those of porridge and nshima made with white maize from week 2 onward. The intakes of porridge and nshima prepared from O1 and O2 did not differ, but intakes became significantly higher when meals made from O3 were introduced (p < .014 for porridge and p < or = .013 for nshima). CONCLUSIONS: These results demonstrate quick adaptation to orange maize, a preference for recently harvested maize, and an optimistic outlook for similar adaptation patterns in other biofortified-maize target countries.

Maize: A Paramount Staple Crop in the Context of Global Nutrition.

The maize plant (Zea mays), characterized by an erect green stalk, is one of the 3 great grain crops of the world. Its kernels, like other seeds, are storage organs that contain essential components for plant growth and reproduction. Many of these kernel constituents, including starch, protein, and some micronutrients, are also required for human health. For this reason, and others, maize has become highly integrated into global agriculture, human diet, and cultural traditions. The nutritional quality and integrity of maize kernels are influenced by many factors including genetic background, environment, and kernel processing. Cooking procedures, including nixtamalization and fermentation, can increase accessibility of micronutrients such as niacin. However, man cannot live on maize alone. For one-third of the world's population, namely in sub-Saharan Africa, Southeast Asia, and Latin America, humans subsist on maize as a staple food but malnutrition pervades. Strategies to further improve kernel macronutrient and micronutrient quality and quantities are under intense investigation. The 2 most common routes to enhance grain nutritional value are exogenous and endogenous fortification. Although exogenous fortification, such as addition of multivitamin premixes to maize flour, has been successful, endogenous fortification, also known as "biofortification," may provide a more sustainable and practical solution for chronically undernourished communities. Recent accomplishments, such as low-phytate, high-lysine, and multivitamin maize varieties, have been created using novel genetic and agronomic approaches. Investigational studies related to biofortified maize are currently underway to determine nutrient absorption and efficacy related to human health improvement.

Suboptimal Vitamin B Intakes of Zambian Preschool Children: Evaluation of 24-Hour Dietary Recalls.

BACKGROUND: Hidden hunger affects individuals who chronically consume an inadequate intake of at least 1 micronutrient and is associated with low dietary diversity. Little data are available on dietary intake or status assessment of B vitamins among preschool children in Zambia. OBJECTIVES: The aim of this study was to assess 24-hour dietary recall records obtained from Zambian children aged 3 to 7 years for B vitamin intake in relation to adequacy and change over time in the same community. METHODS: Twenty-four-hour dietary recalls were collected from 2 studies that were 2 years apart in the same district of Zambia. Data were retrospectively analyzed for B vitamin intake, that is, biotin, vitamin B12, folate, niacin, pantothenic acid, vitamin B6, riboflavin, and thiamin. The estimated average requirement (EAR) cut point method was used to assess inadequacy prevalence for EARs established by the Institute of Medicine in the United States. RESULTS: For all B vitamins, mean values were below the EARs established for children 4 to 8 years old. Relative to the EAR, children had the highest intakes of vitamin B6 with inadequacies of 77.9% and 60.1% in 2010 and 2012, respectively. The highest prevalence of inadequate intake was associated with folate, where ≥95% of the children had intakes below the EAR in both studies. CONCLUSIONS: All median vitamin B intakes were inadequate among these young children in rural Zambia. Future researchers and policy makers may need to consider B vitamin status in resource-poor areas of the country.

Quality protein maize for Africa: closing the protein inadequacy gap in vulnerable populations.

Africa shares a unique relationship with maize (Zea mays). After its introduction from New World explorers, maize was quickly adopted as the cornerstone of local cuisine, especially in sub-Saharan countries. Although maize provides macro- and micronutrients required for humans, it lacks adequate amounts of the essential amino acids lysine and tryptophan. For those consuming >50% of their daily energy from maize, pandemic protein malnutrition may exist. Severe protein and energy malnutrition increases susceptibility to life-threatening diseases such as tuberculosis and gastroenteritis. A nutritionally superior maize cultivar named quality protein maize (QPM) represents nearly one-half century of research dedicated to malnutrition eradication. Compared with traditional maize types, QPM has twice the amount of lysine and tryptophan, as well as protein bioavailability that rivals milk casein. Animal and human studies suggest that substituting QPM for common maize results in improved health. However, QPM's practical contribution to maize-subsisting populations remains unresolved. Herein, total protein and essential amino acid requirements recommended by the WHO and the Institute of Medicine were applied to estimate QPM target intake levels for young children and adults, and these were compared with mean daily maize intakes by African country. The comparisons revealed that ~100 g QPM is required for children to maintain adequacy of lysine, the most limiting amino acid, and nearly 500 g is required for adults. This represents a 40% reduction in maize intake relative to common maize to meet protein requirements. The importance of maize in Africa underlines the potential for QPM to assist in closing the protein inadequacy gap.